涡旋光束的特性及其在光通信的应用

发布时间：2018-08-08 17:31

【摘要】：近几十年,移动通信技术迅猛发展,从2G到目前的4G,通信速率成几百倍的增长,当前社会信息化程度还在不断提升,对通信容量的需求还在与日俱增,为此,如何提高通信容量成为人们关注的焦点。由于涡旋光束是具有螺线形相位分布的光束,其表达式中带有相位因子exp(ilθ),光束中的每个光子携带lη的轨道角动量,其中l称为拓扑荷数,涡旋光束提供了除幅度、频率、相位外的一个新的自由度,即轨道角动量,而且涡旋光束的轨道角动量数在理论上是无限多的,因此将其用于光通信可以大幅提高通信容量。本论文重点对涡旋光束的产生、测量及在光通信的应用做了理论和实验研究。主要内容如下:首先,理论分析了涡旋光束的角动量,介绍了四种常见涡旋光束类型,同时论述了涡旋光束的几种典型应用。其次,介绍了螺旋相位板法产生涡旋光束的原理、实验装置的搭建以及实验产生不同拓扑荷数的涡旋光束,并使用mathcad数学仿真软件对相应拓扑荷数的涡旋光束进行模拟,同时详细分析了叉形全息图的生成原理并进行仿真。再次,从理论和实验两部分研究了倾斜球面透镜测量法测量涡旋光束的拓扑荷数。最后,理论分析了涡旋光束的复用和解复用原理,分析了涡旋光束经叉形全息图的衍射特性并利用数学软件进行模拟,同时利用此特性对涡旋光束进行解复用模拟。在对上述四个方面进行分析和研究,经理论与实验仿真后,提供了一种提升光通信容量的方法和思路。
[Abstract]:In recent decades, the rapid development of mobile communication technology, from 2G to the current 4G, the communication rate has increased hundreds of times, the current level of social information is still improving, the demand for communication capacity is also increasing. How to improve the communication capacity has become the focus of attention. Because the vortex beam is a beam with helical phase distribution, its expression has the phase factor exp (il 胃). Each photon in the beam carries the orbital angular momentum of l 畏, where l is called the topological charge number, and the vortex beam provides the division amplitude and frequency. A new degree of freedom outside the phase is orbital angular momentum and the number of orbital angular momentum of vortex beams is infinite theoretically. Therefore its application in optical communication can greatly improve the communication capacity. In this paper, the generation, measurement and application of vortex beam in optical communication are studied theoretically and experimentally. The main contents are as follows: firstly, the angular momentum of vortex beam is analyzed theoretically, four kinds of common vortex beam types are introduced, and several typical applications of vortex beam are discussed. Secondly, the principle of spiral phase plate method to generate vortex beam, the construction of experimental device and the experimental results of vortex beam with different topological charge numbers are introduced. The vortex beam with corresponding topological charge number is simulated by mathcad mathematical simulation software. At the same time, the generation principle of cross-shaped hologram is analyzed in detail and simulated. Thirdly, the topological charge number of vortex beam measured by inclined spherical lens is studied in theory and experiment. Finally, the theory of vortex beam multiplexing and demultiplexing is analyzed theoretically. The diffraction characteristics of vortex beam through the cross section hologram are analyzed and simulated by mathematical software. At the same time, the demultiplexing simulation of vortex beam is carried out. After analyzing and studying the above four aspects, a method and train of thought for improving the optical communication capacity are provided after theoretical and experimental simulation.
【学位授予单位】：华侨大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN929.1

【相似文献】